A hydronic heat exchanger installed within the sub-floor plenum cools this air down even further using water from a rainwater harvesting tank located beneath the underground parking garage.

St. Alfred’s Anglican Church consists of a main worshipping auditorium, a gathering foyer, meeting rooms, offices and a commercial kitchen as well as an outdoor play and barbeque area. One architecturally unique element of the structure is a 15-inch thick rammed earth wall. The wall not only provides an aesthetically-pleasing backdrop in the worshipping auditorium, but also provides thermal mass which helps to collect heat in the winter and release it into the building. The building is also defined by several other tall walls that feature iconic church symbols and contribute to the natural ventilation system.

The 16,318-square-foot building does not have any air-conditioning – instead, it relies on a complex cooling system that begins with a sub-floor plenum that pulls cool air from an adjacent shaded and irrigated landscaped area. A hydronic heat exchanger installed within the sub-floor plenum cools this air down even further using water from a rainwater harvesting tank located beneath the underground parking garage. The cooled air is then ducted into 10 grilled floor openings throughout the building.

The heating system is equally impressive and is based on a solar chimney integrated into a 45-foot-tall architectural element. The solar chimney gathers heat through north-facing glass located at its base. This heated air is then released through an opening at the top, activating hydronic radiator panels placed throughout the building. The radiator panels work with finned tubes placed in floor openings that are fitted with rock baskets to provide thermal mass. Heated air passes through grates in these floor openings, heating the building during the cool months of the year.